Core C will characterize novel peptides and proteins isolated by the Projects of this Program. In addition, the nature and site of post translational modifications in both novel and recombinant peptides and proteins will be identified. The Core will also perform a variety of services that are essential for the Projects of this Program, including the primary structure determination of synthetic peptides, the chemical characterization of recombinant proteins and the synthesis of oligonucleotides. Chemical sequence analysis and mass spectrometry will be used to characterize the peptides and proteins to be studied. The information obtained from chemical sequence analysis and mass spectrometry is not only complementary but synergetic, especially when investigating structural features of proteins. This synergy becomes particularly important when the amount of sample is limited such as in the characterization of natural products. As all of these investigations require specialized equipment and well trained personnel they ar best centralized in a Core to increase efficiency and to facilitate quality control.